JPH11339138A - Crime prevention system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an erroneous report by executing detection according to the movement of an intruder by plural crime preventing sensors. SOLUTION: Plural crime preventing sensors SA and SB are respectively serially connected through a signal cable L3 and respective sensors SA and SB are in the state of forming a closed loop, and at the time of detecting an intruder, continuously output detecting signals during a prescribed time to the other crime prevention sensor SB or SA through the cable L3. The other sensor SB or SA opens constantly closed contact points (contact point B and contact point A) at the time of detecting the intruder while the detecting signals are outputted, and crime prevention receiver R outputs an alarm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security system configured to monitor a plurality of security sensors in a closed loop.

[0002]

2. Description of the Related Art FIG. 9 is a diagram schematically showing a configuration of a conventional security system. The security receiver R connects a plurality of security sensors (here, two, SA and SB) to the signal line L1.
(Sa, Sb) and the power supply line L2 (+,-), and the sensors SA, SB are connected through the power supply line L2.
Power is being supplied.

The signal line L1 is connected to each security sensor S
A closed loop is formed through normally closed contacts A and SB (contacts A and B), and each of the sensors SA and SB detects a contact when an intruder is detected by a heat ray (infrared ray) emitted from a human body. Is open. Upon detecting the opening of the contact, the security receiver R outputs an alarm sound or a voice message, or displays an alarm by turning on or blinking a lamp to notify an administrator or the like that there is an intruder. .

FIG. 10 is a timing chart showing the operation of the security system. Security sensors SA, S
B immediately opens the respective contacts (contact A and contact B) when the intruder detection input is received, and causes the security receiver R to output an alarm.

[0005]

As described above, in the conventional security system, a plurality of security sensors are connected by a common signal line to form a closed loop and monitor an intruder. But if the security sensor works,
An alarm is output from the security receiver.
Therefore, there is a case where a false alarm is given by the security receiver due to a malfunction of one sensor.

The present invention has been made in view of such circumstances, and has as its object to provide a security system in which a plurality of security sensors perform detection in accordance with the movement of an intruder to prevent false alarms. And

[0007]

In order to achieve the above object, in the security system according to the first aspect of the present invention, each of the plurality of security sensors is connected in series by a signal line,
When each security sensor detects an intruder in a state of forming a closed loop, the security sensor continuously outputs a detection signal to another security sensor via a signal line for a predetermined time, and When an intruder is detected while a detection signal is being output, the security sensor opens a normally closed contact to output an alarm in the security receiver.

That is, according to the present invention, if it is detected that an intruder has moved between two sensors among a plurality of security sensors within a predetermined time, an alarm is output. In the security system according to claim 2, each of the plurality of security sensors is connected in series by a signal line, and each of the security sensors forms a closed loop, and when an intruder is detected, a signal line is provided. Through the other security sensors for a predetermined time,
While continuously outputting the detection signal, when the intruder is detected while the detection signal is continuously output, the normally closed contact is opened and an alarm is output in the security receiver. .

That is, according to the second aspect of the invention, if the intruder is detected again within a predetermined time by the sensor that has detected the intruder, an alarm is output. According to a third aspect, in each of the first and second aspects, each of the plurality of security sensors is provided with setting means for setting a predetermined time for continuously outputting a detection signal to another security sensor in advance. . This setting means may be realized by software such as a memory switch for storing data to be set in a non-volatile memory, in addition to hardware such as a dip switch.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically showing the configuration of the security system. The security receiver R includes a plurality of security sensors (two in this case, SA and SB), an alarm signal line L1 (Sa, Sb), and a power supply line L2 (+,
−), And the security sensors SA and SB are connected to each other by terminals (terminal A and terminal B) provided on each of the sensors SA and SB.
Are connected by a detection signal line L3. That is, in the present invention, in addition to the conventional configuration (see FIG. 9), each of the plurality of security sensors SA and SB is connected in series by the detection signal line L3 which is a signal line.

The security receiver R supplies power to each of the sensors SA and SB through a power line L2. The alarm signal line L1 forms a closed loop via normally closed contacts (contact A, contact B) of the security sensors SA, SB. Each of the security sensors SA and SB detects an intruder by a heat ray (infrared ray) or the like emitted from the human body, and detects the intruder in a state where a closed loop is formed by the alarm signal line L1. Sometimes, via the detection signal line L3, the other security sensors SB and SA
The detection signal is continuously output for a predetermined time. And
When the other security sensors SB and SA detect an intruder while the detection signal is being output through the detection signal line L3, they open the normally closed contacts (contact B and contact A) and output the security receiver R To output an alarm.

That is, in the security receiver R, the sensors SA and SB are connected to the contacts (contacts A and A) through the alarm signal line L1.
When detecting that the contact B) has been opened, an alarm is output.
The alarm at the security receiver R outputs an alarm sound composed of an electronic sound such as "boo" or "There is an intruder."
This is performed by outputting a voice message, turning on or blinking a lamp, or displaying an alarm message on a display.

When the administrator or the like knows that there has been an intruder by this alarm, he confirms the site where the security sensors SA and SB that have issued the alarm are installed. Call the police. In the present invention, as shown in FIG. 2, two sensors S out of a plurality of security sensors are used.
If it is detected that the intruder M has moved between A and SB within a predetermined time, an alarm is output. No alarm is output.

In the above, the case where the security sensors SA and SB that first detect an intruder and the security sensors SA and SB that detect an intruder are different has been described.
The present invention is not limited to this, and the same sensor may operate in the same manner even when the intruder is detected twice. In this case, when each of the security sensors SA and SB forms a closed loop with the alarm signal line L1 and detects an intruder, the security sensors SA and SB are connected to the other security sensors SB and SA through the detection signal line L3. When the intruder is detected while the detection signal is continuously output for a predetermined time and the detection signal is continuously output, the normally closed contacts (contact A and contact B) are opened to prevent crime. An alarm is output at the receiver R.

Thus, even if the intervals between the security sensors SA and SB are wide and the intruder does not move from one place, the intruder can be detected and an alarm can be output. FIG. 3 shows an example of a circuit configuration of the security sensors SA and SB. As shown, the security sensor S
A and SB each include a CPU 1, and control opening and closing of a contact A or a contact B by a contact circuit 2, and control output of a detection signal from the terminal A or the terminal B by a terminal circuit 3.

Here, a predetermined time for continuously outputting a detection signal from the terminal A or the terminal B to the other security sensors SB and SA can be set in advance. A dip switch SW is provided. The set predetermined time may be set to a time sufficient for detecting that the intruder has moved. Therefore, when the interval between the security sensors SA and SB is wide, a relatively long time is set. If the installation interval is narrow, a relatively short time may be set.

The setting means may be a software such as a memory switch for storing data in a non-volatile memory, other than a hardware such as a dip switch or a dial switch.
In the contact circuit 2, since the contact output port P1 of the CPU 1 is always at the H level when there is no detection input, the current Ib limited by the resistance values of the resistors R2 and R3 flows through the transistor Tr1. When Ib flows, Tr1
Turns on and the current Ic limited by the resistor R1
Flow. Ry closes the contact A or the contact B while Ic is flowing. When the contact output port P1 becomes L level due to the detection input, Ib stops flowing, Tr1 turns off, and Ic turns off. Stop flowing, Ry
Opens contact A or contact B.

On the other hand, in the terminal circuit 3, since the terminal output port P2 of the CPU 1 is always at the H level when there is no detection input, the transistor Tr1 is turned on.
The current Ic limited by the resistance value of the resistor R4 flows. While Ic is flowing, the terminal a of the contact A or the contact B is at the ground level. However, when the terminal output port P2 becomes L level due to the detection input, Tr2 is turned off, and Ic stops flowing, and the contact A or the contact A Terminal a of contact B
A voltage of Vcc appears on the display.

FIG. 4 is a timing chart for explaining the operation of the security system described above. FIG. 4 (a)
FIG. 4B shows a case where the intruder M moves as shown in FIG. 2 and outputs an alarm, and FIG. 4B shows a case where the alarm is not output because it is determined that the sensor malfunctions. In (a), after the security sensor SA detects an intruder, it outputs signals to the terminals A and B. If the security sensor SB detects the intruder within a predetermined time T, the contact B is opened to open the contact. An alarm is output from the receiver R. Here, at the same time as the contact B, the sensor SA
Contact A is also open.

On the other hand, in (b), after the security sensor SA detects the intruder, it outputs signals to the terminals A and B. After a predetermined time T, when the security sensor SB detects the intruder, It is determined that the detection input of the sensor SA is caused by a malfunction, the contact B is not opened, and the signal output for the predetermined time T to the terminals A and B is started again. As described with reference to FIG. 3, the contact output from the port P1 of the CPU 1 is always at the H level, and when the output is at the L level, the contact is opened. On the other hand, the terminal output from the port P2 is always at H level, and when it is at L level, the detection signal line L3
The signal is output through.

Although the case where two security sensors SA and SB are connected to the security receiver R has been described above, the present invention is also applicable to a security system having three or more security sensors. it can. FIG. 5 is a diagram schematically illustrating a configuration of a security system including three security sensors.

The security receiver R connects the security sensors SA, SB, SC to the alarm signal line L11 (Sa,
Sb) and the power supply line L12 (+,-), and the security sensors SA, SB, SC
Terminals provided on B and SC (terminal A, terminal B, terminal C)
Are connected in series by the detection signal line L13.
The security receiver R supplies power to each of the sensors SA, SB, SC via a power supply line L12. The alarm signal line L11 forms a closed loop via normally closed contacts (contact A, contact B, contact C) of the security sensors SA, SB, SC.

When each of the security sensors SA, SB, SC forms a closed loop with the alarm signal line L11 and detects an intruder, the detection signal line L13
, The detection signal is continuously output to the other security sensors SA to SC for a predetermined time. In the other security sensors SA to SC, when an intruder is detected while the detection signal is being output through the detection signal line L13, the normally closed contacts (contacts A to C) are opened and the security reception is performed. An alarm is output at the machine R.

Therefore, as shown in FIGS. 6A and 6B, if it is detected that an intruder has moved between two or more sensors among a plurality of security sensors within a predetermined time, Output an alarm. FIG. 6 is a diagram when the ceiling surface is looked up from the floor surface. In the figure, the movement of the intruder on the floor surface is indicated by an arrow. Also, in this configuration,
The security sensors SA to SC that first detect an intruder and the security sensors SA to SC that detect an intruder next may be the same. In this case, when each of the security sensors SA to SC forms a closed loop with the alarm signal line L11 and detects an intruder, the detection signal line L13
, The detection signal is continuously output to the other security sensors SA to SC for a predetermined time, and when an intruder is detected while the detection signal is continuously output, the sensor is normally closed. The contacts (contacts A to C) are opened to output an alarm in the security receiver R.

FIGS. 7 and 8 are timing charts for explaining the operation of the security system provided with the three sensors SA to SC described above. FIG. 7 shows a case where the intruder moves as shown in FIG. 6A, and FIG. 8 shows a case where the intruder moves as shown in FIG. 6B. In FIG. 7A, after the security sensor SA detects the intruder, the terminal A, the terminal B, and the terminal C are detected.
Within a predetermined time T during which a signal is output to the security sensor SB
Detects an intruder, opens the contact B, and causes the security receiver R to output an alarm. Here, the contact A of the sensor SA and the contact C of the sensor SC are open at the same time as the contact B.

On the other hand, in FIG. 7B, after the security sensor SA detects the intruder, it outputs signals to the terminals A, B, and C for a predetermined time T, and then the security sensor SB detects the intruder. In this case, it is determined that the sensor SA has malfunctioned, the contact B is not opened, and the terminals A, B,
The signal output to the contact C for a predetermined time T has started. In addition,
The contact output from the port P1 of the CPU 1 is always at the H level, and when the output is at the L level, the contact is opened. on the other hand,
The terminal output from the port P2 is always at the H level, and when it is at the L level, a signal is output through the detection signal line L13.

In FIG. 8A, after the security sensor SA detects an intruder, the security sensor SC detects the intruder within a predetermined time T during which signals are output to the terminals A, B and C. The contact C is opened to output an alarm from the security receiver R. Here, at the same time, the contact A of the sensor SA,
The contact B of the sensor SB is also open. Subsequently, FIG.
Then, after the security sensor SC detects the intruder, the terminal A,
After outputting a signal to terminal B and terminal C for a predetermined time T,
The security sensor SB detects an intruder, and in this case,
The contact B is not opened, and the signal output for the predetermined time T to the terminal A, the terminal B, and the contact C is started again.

Unlike the figure, when the security sensor SB detects an intruder during the predetermined time T during which the detection signal is being output, the contact B is opened. At this time, if the security receiver R has already output an alarm, the alarm may be continuously output.

[0029]

As can be understood from the above description, in the security system according to the first aspect of the present invention, when each security sensor detects an intruder before the other security sensors, it detects other The security sensor outputs a detection signal for a predetermined time, and the other security sensors open the normally closed contact when an intruder is detected while the detection signal is being output.
An alarm is output from the security receiver. That is,
When detecting that an intruder has moved between two or more sensors among a plurality of security sensors within a predetermined time, an alarm is output. Therefore, unlike the related art, the erroneous operation of one sensor does not cause the security receiver to erroneously output an alarm.

In the security system according to the second aspect, when each security sensor detects an intruder before the other security sensors, it outputs a detection signal to the other security sensors for a predetermined time. When the intruder is detected again while the detection signal is being output, the normally closed contact is opened, and the security receiver outputs an alarm. Thus, even if the installation interval of the security sensors is wide and the intruder does not move from one place, the intruder can be detected and an alarm can be output.

In the third aspect, each security sensor has
Since a predetermined time for continuously outputting the detection signal to another security sensor can be set, a highly reliable security system can be provided according to the environment.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a configuration of a security system according to the present invention.

FIG. 2 is a diagram illustrating an example of movement of an intruder in the security system of FIG. 1;

FIG. 3 is a circuit diagram showing an example of an internal configuration of the security system of FIG. 1;

FIG. 4 is a timing chart showing an example of the operation of the security system of FIG. 1;

FIG. 5 is a diagram schematically showing another configuration of the security system of the present invention.

FIG. 6 is a diagram illustrating an example of movement of an intruder in the security system of FIG. 5;

FIG. 7 is a timing chart showing an example of the operation of the security system of FIG. 5;

FIG. 8 is a timing chart showing another example of the operation of the security system of FIG. 5;

FIG. 9 is a diagram schematically showing a configuration of a conventional security system.

FIG. 10 is a timing chart showing the operation of the conventional security system.

[Explanation of symbols]

R Security receiver SA, SB, SC Security sensor L1, L11 Alarm signal line L3, L13 Detection signal line 1 CPU 2 Contact circuit 3 Terminal circuit SW Dip switch T Predetermined time to output detection signal continuously

Claims (3)

[Claims] 1. A security system comprising a plurality of security sensors and a security receiver formed by connecting the security sensors through a normally closed contact of each security sensor to form a closed loop. Each of the security sensors is further connected in series by a signal line, and each of the security sensors forms the closed loop,
When an intruder is detected, the detection signal is continuously output to another security sensor through the signal line for a predetermined time, and the other security sensor outputs the detection signal. When an intruder is detected while the
A security system, wherein the security receiver outputs an alarm. 2. A security system comprising: a plurality of security sensors; and a security receiver formed by connecting the security sensors through a normally closed contact of each security sensor to form a closed loop. Each of the security sensors is further connected in series by a signal line, and each of the security sensors forms the closed loop,
When an intruder is detected, the detection signal is continuously output to another security sensor via the signal line for a predetermined time, and while the detection signal is continuously output, When an intruder is detected, a normally closed contact is opened to output an alarm in the security receiver. 3. The security sensor according to claim 1, wherein each of the plurality of security sensors is provided with setting means for setting a predetermined time for continuously outputting a detection signal to the other security sensors. Security system described in.